Nonwoven fabrics have wide applications including clothes, disposable diapers and personal hygiene products. The nonwoven fabrics for such applications are required to have excellent properties, such as touch, conformability to the body, conformity during body movements, drape, tensile strength and surface abrasion resistance.
Traditional nonwoven fabrics made from a monocomponent fiber, while being resistant to fuzzing and comfortable to the touch, are unsatisfactory in extensibility. Accordingly, there has been a difficulty in using such nonwoven fabrics in diapers and the like where both comfortable touch and good extensibility are required.
It has been believed that the nonwoven fabrics are desirably imparted with elastic properties in order to meet the above requirements, and various methods have been proposed for imparting elastic properties. For example, mechanical stretching of composite nonwoven fabrics that include at least one elastic layer and at least one substantially inelastic layer can produce elastic properties. However, the composite nonwoven fabrics by this method have problems in that the inelastic fiber is damaged or broken during the mechanical stretching to produce fuzz and the fabric strength is lowered.
In consideration of such problems, studies have been being carried out in order to impart high extensibility to the inelastic fibers. For example, JP-A-9/512313 and WO 01/49905 propose composite nonwoven fabrics that comprise multipolymer fibers containing two or more different polymers as the inelastic fibers. The multipolymer fibers contained in the composite nonwoven fabrics have achieved high extensibility. However, the composite nonwoven fabrics according to the teachings of these publications suffer fuzzing and have inferior touch.